1. Field of the Invention
The present invention relates to a connection for transferring lubricant across a moving interface between parts. In particular, the present invention relates to a lubricant transfer bushing for transferring lubricating grease between a lubricant line in a cylinder body of a high-speed combination folder for a printing press and a cam follower movable relative to the cylinder body.
2. Description of the Prior Art
In high-speed combination folders used with printing presses, it is known--as shown in FIG. 7--to provide a cylinder 100, a shaft 15 and a cam follower 1 which is mounted for pivoting movement relative to the shaft 15. Cylinder 100 rotates in direction D. As is known in the prior art, these cam followers 1 experience high loads and high rotational speeds; as a result, the follower must be lubricated for proper operation. Prior art folders have used two methods for lubricating the cam follower: sealed cam followers and relubricatable cam followers.
Sealed cam followers use a lubricant--typically, grease--which is sealed within the cam follower and not replenished during operation. A disadvantage of sealed cam followers is that if the lubrication heats up sufficiently to liquefy (i.e., at temperatures roughly greater than 70.degree. C.), it may flow past the seals, thereby decreasing the amount of lubrication and potentially resulting in seizing of the cam follower.
Because of the above-described disadvantages of the use of sealed cam followers, certain prior art cam followers 1 (as shown in FIG. 7) have been manufactured to be relubricatable. A typical prior art relubricatable cam follower 1 arrangement includes lubricant supply lines 102 which are connected, via flexible plastic tubing 101 spanning the dynamic interface between moving parts (i.e., between supply housing 22 and cam follower lever arm 5), to a lubricant inlet port in the cam follower lever arm 5. The lubricant inlet port is connected to internal lubricant channeling holes or grooves in the cam follower lever arm 5 and the cam follower 1, which act to transfer the lubricant from the lubricant inlet port to the cam follower 1, thereby providing a continuous source of lubricant to the cam follower 1.